Cryptic crossword No 3,143

Across

1. Natural alternative finally making America 60% nicer (7)
2. Thick milky juices from some plants found in flat ice sheets (7)
3. Grape growers mixing any red inside six seconds (9)
4. Online rag misrepresented structural element? (5,4)
5. Working on installing one bulb (5)
6. Spooner's son observed to get edamame? (3,4)
7. At no time run after regular boomerangs! (5)
8. Police transport damaged polar cart (6,3)
9. Scruffy hare by heel of pheasant beater (5)
10. Unofficial consumption tax secured by regular letters from appraiser (7)
11. The girl desires ditching old bookcase parts? (7)
12. Popular and very liberal blue sadly impossible (9)
13. Bill enshrines right and starts to deliver on means for autonomy (7)
14. Best of jam containing tip of elderflower (5)
15. Ship featured in reference book after half of crew betrayed (7)
16. Promote team losing final point, bringing in former volunteers on return (7)

Down

1. Banning success secured by convict following naked youth (9)
2. Nick gets house piano (3,4)
3. Boisterous number is unknown (5)
4. Raised section of masterpiece inspired relative (5)
5. Wooded areas beneficial to homes having no neighbours initially (7)
6. American nerd we put in propped up bed (5)
7. Conspicuous old boy introduces five obligations (7)
8. Prime former prison space with facelift at last (9)
9. Politicians perhaps recall banishing soldiers beginning to shoot (7)
10. Daughter lost by careless cave divers or the other way round? (4,5)
11. Confident knight heard with leaders of the army in negotiation (7)
12. Food passage absorbing gas from the bottom (7)
13. Curious holy man conducted grace on vacation (7)
14. Heavy industries essentially unfashionable (5)
15. Loveless Colin being thrown in river for failure (7)
16. Anyone carelessly straddling toilet with its lid down creates nuisance (9)